Christoph M. Wintersteiger Youssef Hamadi Leonardo Mendonça de Moura A Concurrent Portfolio Approach to SMT Solving. 715-720 2009 CAV http://dx.doi.org/10.1007/978-3-642-02658-4_60 conf/cav/2009 db/conf/cav/cav2009.html#WintersteigerHM09